The Spiral Politic was a symbolic map of history, with the Homeworld at its centre, used to visualise the state of four-dimensional reality during the War in Heaven. Because it was a map of the universe, "the Spiral Politic" was sometimes used as a metonym for the Great Houses' universe itself, for example to distinguish it from the Spiral Yssgaroth of their vampiric enemies. It could also be used as a byword for the meta-structure of history itself.
The Spiral Politic did not reflect straightforward physical or even temporal positions; instead, the distance between two given planets on the map was a function of how closely causally related their timelines were. Thus, the Homeworld was immediately surrounded by a core set of worlds over which it had the most influence, locked into place as protections against the uncertainty outside. Like any noosphere, the Spiral Politic had an edge, the frontier in time, beyond which the Great Houses had great difficulty penetrating or even observing. Worlds made up the majority of historical systems on the map of the Spiral Politic, but there were some significant exceptions: these included regions outside normal time, like the Eleven-Day Empire and the City of the Saved, as well as a rare few individuals of blinding historical importance.
Early in the War in Heaven, the enemy would often drastically alter certain worlds' relationships with history. On the map of the Spiral Politic, these previously-static worlds would appear to suddenly shoot across the chart. If one of these "shooting star" worlds collided with the Homeworld, it could take the Homeworld's place and retroactively replace it as the centre of history, wiping the Great Houses and their influence from the timeline. (PROSE: The Book of the War)
Iris Wildthyme derisively called the Spiral Politic the "Tale Without Meaning". (PROSE: First Meetings)